Centrifugal switch



Patented Nov. 9, 1926.

` JoIIN 'I'. amarre. or CHICAGO, ILLINOIS.

PATENT. oFFl-CE.

l CENTBIFUGAL SWITCH.

Application mea Marca ao, 1925. serial No. 19,403.

lThis-'invention relates to centrifugal or automatic switches adapted for use in con-v nection with electriczmotors and more particularly with such motors of the split phase alternating current type. The mvention relates to the generalconstruction of such switches', but it is particularly directed to the' mountin of the 'weights and the arrangement o the contact disk and supportl in parts. f

e objects of this "invention are to provide an'improved centrifugal switch which is adapted to be actuated when the rotor or part upon which it is mounted' reaches a l predetermined speed; toprovide pivoted arm supports for the weights which will have little or no tendency toward binding and which are rovided with. interlocking portions toi limit the opening and closing movements; to provide a reversible contact disk with means for supporting the same and means for causing the sup orting means to rotate with the2 rotor sha to lprovide a'spring tension for holding the weights in normal position and means whereb the tension will be decreased as the weights swing outwardly; to provide an auxiliary spring for holding 4the contact disk against the stationary contact brushes; and to provide such other novel features and advantages as will be described hereinafter.

In the accompanying drawings illustrating this invention,

Figure 1 is a side view showing a rotor or y armature with my improved switch applied thereto;

Figure2 isa sectional view taken on the line 2-2 of'Figure 1,

Figure 3 is a sectional view taken onthe y line 3-3 of Figure 2; and

Fi reV 4 is a view simllar to Figure 1,

showing` the switch opened, that is with thev weights in extended position andthe contact disk drawn away from the stationary contacts.' l v The switch is shown applied to a rotor 5 of any suitable constrction, which is mounted on a'shaft 6. The -disk or movable switch member 7 Ais rotatably mounted on' a sleeve or collar 8, which is adapted to slide freely on the' shaft 6, and is insulated therefrom. Thef insulating disksy or supports 9 are held on the sleeve 8 by meansof .springrings 10l andllsf The-contact disk or switch member 7 is'normally heldlagainst the'ixed brushes or contacts 12 and 13 by a spring 14 which engages with one end of the sleeve 8 and abuts at the other end against the rotor'5.

ik plate 15 is secured tothe rotor and has palrs of ears or bearings 16 and 17 which are diametrically opposed to` each other.

Pins 18 and 19 arecarried respectively by .I

the ears 16 and 17, and form pivots for the .oppositely disposed pairs of weight supporting arms or levers 20 and 21. The arms 20 are secured to or formed integrally with aplatev or segment 22 to which is secured the weight 23. The arms 21, which are duplicates of the arms 20 are also connected with a plate 24 to which is secured the second weight 25.' The arms 20 and 21 pivoted ends of the' arms 20 and 21. The l plates or segments 22 and 24 are provided respectively with pairs of ears or. lugs 28 and 29 which extend laterally ortoward the arm pivots. These opposed lugs are connected by'tension springs 30 on opposite sides of the shaft, which tend to drawfthe segments and connected parts toward the shaft or center. It will be noted on account ofi.pos'itioning the springs rearwardly or adjacent to the pivots, the weights will have a differential action on the springs so that as the weights move outwardly and the springs move toward the pivots, the force necessary to overcome the tension of the springs will be gradually decreased, due to the toggle or leverage action.

I; have found it desirable'to cause the sleeve .8 to be rotated with the shaft so that A from the segments 22 and 24 and are :flare provided on the opposite sides with co- -acting lugs or stops 26 and 27 which limit -thev inward or closmg movement thereof, as

los

substantially parallel to the shaft 6. These fingers are provided with shoulders y34:

the contact disk 7 is permitted to .engage` with the fixed contacts, under the action of the sprin'i; 14, shortly -before the weights reach their'innermost position. As lon -as the weights are in such position, the isk will remain in engagement with the contacts, but as soon as the speed of the motor reaches a predetermined point, the weights will swing outwardly andttoward the rotor. This will cause the shouldersl 34 to press -against .the projections 31 and move the sleeve backwardly, so that the disk is withdrawn from the stationary contacts and the switch is opened. On account of pivoting the levers on opposite sides of the shaft so that they extend across the shaft to support a weight on the opposite side, the length ofthe levers is increased, which tend to vprevent binding and improves the opening movement of the switch. It will also be noted that when the contact diskf? becomes worn on one side,-.-it may be readily reversed so that the opposite side may be used for making contact.

My improved switch may be made in various sizes and the parts may be modified in order yto adapt it to different types of motors or other devices in which a centrifugal switch may be utilized and therefore I vcarried by the sleeve, the disk from the sleeve, a spring tending do not wish to be limited to the exact con-v struction herein shown and described except as ointed out in the following claims, i'n which I claim: v y

1'. A centrifugal switch construction comprising a rotatable shaft, a sleeve loosely mounted on said shaft, a reversible contact disk carried by said sleeve Aand insulated therefrom, means for holding said sleeve and disk in normal' engagin position, and

rotatable means adapted to e actuated byf centrifugal force for moving the sleeve and disk out of engaging position.

2. In a vdevice as'per claiml, the combination with a sleeve, of a reversible contact disk, means for insulating the disk. from the sleeve,and'l spring rings for holding the disk onthe sleeve.

3. In a switch construction, the combination with al rotor and its shaft, of a sleeve slidably mounted on the shaft, a contact disk means for insulating to hold the sleeve with the disk in normal .engaging position, arms pivotally secured to the rotor and projecting across to .the

opposite sides of the shaft, weights carried by said arms, means for connecting the arms .withjthe sleeve, whereby the sleeve' will be moved'out of engaging position when the arms swing outwardly, and yielding extending outwardly from said the ,combination of a rotatable member, `a

shaft carrying said member, a sleeve on said shaft, a contact carried -by\the sleeve and f im adapted to engage with fixed contacts adjacent to the shaft, pairs vof armspivotally secured to the rotatable member on opposite sides of4 the shaft and extending across the shaft crossing each other and provided with 'interlocking stops, vweights secured to the free ends of the pairs of arms, sprin s con# nected withthe ends of the arms an ing to draw them toward the shaft, and -means for connecting the arms with the sleeve to cause the sleeve to movelongitudinally of the shaft when the arms are swung on their pivots.

5. In a switch construction, the combina'- tion with a rotor and its shaft, of a sleeve mounted for longitudinal movement on the shaft, a spring interposed betweenthe sleeve and the rotor, means for causing the sleeve to .rotate with the shaft, a contact disk rotatably mounted on the sleeve and, free from said spring, which spring tends to hold the disk in engaging position, and centrifugally operated means for moving the sleeve longitudinally of the shaft. l* 6. In a switch construction, the combination with a rotatable member and its supporting shaft,- of a sleeve mounted on said shaft,a contact disk'rotatably mounted on the sleeve and adapted. to make contact with fixed contacts adjacent to the shaft when the sleeve is in normal position, a pair of arms pivotally secured to the rotatable member and extending across the shaft, a` plate' connecting the free ends of the arms, aweight secured to said plate, a second pair of a tendshaft, the arms on opposite sides of theics pivotally secured to the rotatable mem rb e ends of saidvlast namedar'ms,

a.' weight secured to said plate, fingers projecting from the plates toward the pivots, springs connecting said fingers for drawing the ends of the arms inwardl projections sleeve and having slot-s in the ends thereof, shouldered tongues on the plates for engagement with said projections to cause the sleeve to rotate with the shaft and also to move .the sleeve longitudinally of the shaft, and stops on the arms for limiting the swinging. movement thereof.

7. A device as per claim 6, havin crossed pivoted weightsuppoliting arms an springs associated with the arms and adapted to move toward the pivots when the arms swing outwardly, whereby thepower necessary ,to be exerted by the arms for opening the same `against the tension of the springs will be decreased as the free ends of the arms swing outwardly.v

8. A device as per claim 6 having pairs of integrally formed Weight supporting plates and arms which are duplicates of each other, said arms having interlocking projections for limiting the movements thereof.

9. In a centrifugal switch construction, the combination of a rotatable shaft, of a movable contact" slidably mounted on the shaft and adapted to engage with fixed contacts, .yielding means tending to hold the movable contact in engagement with the fixed contact, and centrifugal means for withdrawing the movable contact from the fixed contacts to yopen the switch, the arrangement being such that the pressure on the contacts is independent 'of the switch opening means.

l 10. A centrifugal starting switch, comprising a slidable contact support, a contact.

insulated from said support, a spring tendingto move said contact support to contacting position, a rotatable member, weights 1pivotally mounted on said member, springs tending to hold said weights in retracted position, means connecting the weights and the contact carrier wherebythe carrier will be moved b v the swinging movement o\f the weights and a stop for limiting the inward movement 4of the weights whereby the A switch will be closed under tension of the first mentioned spring only.

JOHN T. JANETTE.. 

